Description

Sodium Sulfite is an essential inorganic compound widely used as a versatile reducing agent and preservative. Its ability to scavenge oxygen and inhibit oxidation makes it a critical component for maintaining product stability and quality across numerous industrial processes. Key industries that rely on this chemical include water treatment, pulp & paper manufacturing, photography, and food processing, where it ensures operational efficiency and product integrity.

Application

• Water Treatment: Acts as an oxygen scavenger in boiler feed water and municipal water systems to prevent corrosion and scale formation.
• Pulp & Paper Industry: Used in the sulfite pulping process and as a bleaching agent to delignify wood pulp and enhance paper brightness.
• Photographic Development: Serves as a preservative in developing and fixing solutions to prevent oxidation and extend chemical shelf life.
• Food Preservation (FCC Grade): Approved as an antioxidant and preservative (E221) to prevent discoloration and spoilage in dried fruits, wines, and other food products.
• Chemical Manufacturing: Employed as a reducing agent and sulfonation agent in the synthesis of various chemicals, including dyes and pharmaceuticals.
• Textile Processing: Utilized as an antichlor to remove excess chlorine after bleaching, protecting fabric fibers.
• Mining & Metallurgy: Applied in ore flotation and as a precipitating agent in the recovery of precious metals.
• Dechlorination: Effectively neutralizes chlorine and chloramines in effluent streams for environmental compliance.

Basic Information

Product Name	Sodium Sulfite
CAS No.	91829-63-9
Molecular Formula	Na2SO3
Molecular Weight	126.04 g/mol
Synonyms	Disodium sulfite; Sulfurous acid, disodium salt; Sodium sulfite anhydrous; Exsiccated sodium sulfite; Natrii sulfis; E221
EINECS	Contact for details

Quality Control

Our Sodium Sulfite is manufactured under strict quality management systems to ensure batch-to-batch consistency and reliability. We offer various grades, including Technical, Food (FCC), and Photo grades, each meeting stringent specifications. Certificates of Analysis (COA) documenting purity, assay, and impurity profiles are provided with every shipment to guarantee compliance with your application requirements.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). This product is hygroscopic (moisture-sensitive) and easily oxidized; therefore, containers must be kept tightly sealed when not in use to minimize exposure to air and moisture. Store away from strong acids and oxidizing agents.

Specification

Item	Specification
Appearance	White crystalline powder
Identification (IR)	Conforms
Assay (Na2SO3)	≥ 98.0 %
pH (5% solution)	9.0 - 10.5
Water Insoluble Matter	≤ 0.01 %
Heavy Metals (as Pb)	≤ 10 ppm
Iron (Fe)	≤ 5 ppm
Selenium (Se)	≤ 10 ppm

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.